At the present time, there is a scarcity of insulation widely used in walls of homes and other buildings, of the type wherein fibrous material, such as fiberglass or asbestos, is contained within a paper and/or aluminum covering which has projecting strips along opposite edges for nailing or stapleing to the studs or other frame members of the vertical walls of a building. Because of the current energy shortage, it is important that homes and other buildings be insulated properly during construction in order that as much heat and cooling can be conserved as is reasonably possible. Also, from the standpoint of economy in use of the building, the provision of adequate insulation is important. Loose insulation can be blown into walls which have been completed at both their outer and inner sides, but this manner of installation of insulation leaves something to be desired, in that cavities in the insulation can result, and in that no vapor barrier is provided by the insulation in addition to those normally provided, and in that settling of this type of insulation can be severe over a period of time so that the insulation becomes less effective. The present invention provides methods and apparatus so that adequate insulation can be efficiently and economically provided in walls despite the shortage or unavailability of the covered or bagged types of insulation heretofore employed.